This study is focusing on patients presenting with suspected malignancies of the pituitary gland who are considered to be good surgical candidates.The primary end-point of the study is to determine the sensitivity of OTL38 uptake and expression in identifying those nodules when excited by an imaging probe.There will be a single dose of 0.025 mg/kg for intravenous injection over approximately 60 minutes, two to three hours, prior to surgery.